1. Field of the Invention
The present invention relates to an electromagnetic sound generating body incorporated in mobile communications devices, such as cellular phones and pagers, that generates an incoming call indicator tone when the device receives an incoming call.
2. Description of the Related Art
A known example of the conventional electromagnetic sound generating body of this kind is a buzzer 1 which is thin and has a vibratory sound generating unit (not shown) incorporated in a rectangular parallelepiped resin casing 2 shown in FIGS. 1 and 2. The buzzer 1 is surface-mounted on a printed circuit board 4 and incorporated in a exterior case 3 of, for example, a cellular phone. The casing 2 has a sound release hole 5 formed in the front side thereof, which is arranged coaxial with an external sound release hole 6 formed in the exterior case 3. To prevent the incoming call indicator tone released from the sound release hole 5 of the buzzer 1 from becoming trapped inside the exterior case 3, a sound leakage prevention packing 7 is provided in a gap between the sound release hole 5 and the external sound release hole 6 of the exterior case 3.
In the conventional buzzer 1, however, because external connection terminals 8 are formed at four corners of the casing 2 and directly soldered to the wiring pattern on the printed circuit board 4, vibrations of the buzzer 1 propagate to other electronic components and circuits mounted on the printed circuit board 4, producing noise in these electronic circuits and components.
Further, because the buzzer 1 is surface-mounted on the printed circuit board 4, if the printed circuit board 4 is deviated from the correct mounting position when assembled into the exterior case 3 of a cellular phone, the sound release hole 5 of the casing 2 fails to align coaxially with the external sound release hole 6 of the exterior case 3, resulting in the incoming call indicator tone being trapped inside the exterior case 3.